1. Field of the Invention
The present invention relates to an optical disc apparatus provided with a disc tray to load in and to carry out an optical disc medium that is a recording medium.
2. Description of Related Art
Recently, an optical disc apparatus has been widely used, in which light is irradiated onto a recording surface of an optical disc medium to perform recording of information or reproducing of information. The optical disc apparatus includes a chassis utilized as a housing, and a disc tray provided for the chassis so as to be moved in or out of an opening formed in front of the chassis.
When the disc tray protrudes most outside of the chassis from the opening, the disc tray is located at a disc loading position where the optical disc medium is loaded on or off. The optical disc medium is placed on the disc tray, and the disc tray is moved into the inside of the chassis so as to load the optical disc medium inside of the chassis. When recording/reproducing of information is completed, the optical disc medium is returned on the disk tray. The disc tray on which the optical disc medium is placed is moved outside so as to carry the optical disc medium out of the chassis.
Each of the sides of the disc tray includes a rail extending in sliding direction. The chassis includes support portions for supporting a lower surface of the rail and pressing portions for pressing an upper surface of the rail. The disc tray is slid while the rails are supported by the support portions. The upper surface of the rail is pressed by the pressing portions so that the disc tray is suppressed from floating. Spaces are typically formed between the pressing portions and the upper surface of the rail for reducing friction while the disc tray is slid.
Hereinafter, the disc tray will be explained. When the disc tray protrudes most outside of the chassis from the opening, the gravity point of the disc tray is outside of the chassis. At this time, a protruding end part of the disc tray inclines downwards, and the upper surface of the rail is in contact with the pressing portions. This inclination is due to the weight of the disc tray itself and the weight of the optical disc medium if the optical disc medium is placed.
It is confirmed that when the disc tray is moved into the chassis and the gravity point passes the opening, the disc tray is abruptly returned from an inclined state to its former angle by the movement of the gravity point. Such abrupt change of an attitude of the disc tray is a cause to decrease remarkably the quality of the optical disc apparatus.
Accordingly, a disc apparatus described in JP-A-2007-200507 includes a guide rib and an inclination absorbing rib both of which are in contacted with the upper surface of the guide rail formed on the tray so as to suppress the abrupt change in the attitude. Each of the guide rib and the inclination absorbing rib is formed by an inclined surface having a lower surface formed to be gradually lowered in the inserting direction of the tray. When the tray is moved from outside into inside of, a rear end of the guide rail is smoothly guided by the inclined surface, and therefore the abrupt change of the attitude of the tray is suppressed.
The abrupt inclination of the disc tray when moving can be suppressed by the disc apparatus disclosed in JP-A-2007-200507. However, it is difficult to suppress downward inclination of the protruding end of the disc tray when the disc tray protrudes outside of the chassis.
Furthermore, in the disc tray, positions of the gravity points of the disc tray are different from each other among the case where the optical disc medium is not placed, a case where the optical disc medium with a diameter of 12 cm is placed, and a case where the optical disc medium with a diameter of 8 cm is placed. If the positions of the gravity points of the disc tray are different from each case, positions where the abrupt inclination of the disc tray occurs are different. If using the inclination absorbing rib disclosed in JP-A-2007-200507, it might be difficult to suppress the abrupt inclination of the disc tray when a different sized optical disc medium is placed, or when an optical disc medium is not placed.